Lewis Hamilton thinks the Red Bulls will be tough to beat over the remainder of the season and says he is now being realistic about his chances in the championship after finishing fifth at the Japanese Grand Prix.

Fernando Alonso's retirement at Suzuka means Hamilton has closed the gap to the championship leader by 10 points to 42, but he also lost ground to race winner Sebastian Vettel who is four points off Alonso. Hamilton said he would not give up on chasing down the title in the remaining five races but admitted it would be tough.

"I'm quite a realistic person so I know my situation, but I'll never give up," he said. "We've had some strong results and Jenson did good job today and with better qualifying we would have had a better result. But the Red Bulls will be tough to beat."

Hamilton felt fifth place was as high a position as he could have hoped to achieve on Sunday after struggling with the setup of his car all weekend.

"It wasn't particularly exciting but I think I got everything I could from the car," he said. "It's just a little bit strange, the car's behaviour this weekend, I had this understeer through qualifying and today was the same. I thought with the wind direction it would change but it started off the same as qualifying, so I was falling back from the grid and wasn't quick enough. Then all of a sudden I had this thud on the rear on lap 20 or something and all of a sudden the car started turning and after that I was able to push. I don't know why that was but we'll try to find out why."

Paul Pogba said he left Manchester United because he was "disgusted" Sir Alex Ferguson picked a right-back ahead of him in midfield and revealed it caused the breakdown of his relationship with the former manager